Bitting configurations on keys are often utilized to control the operation of lock mechanisms. More specifically, the configuration of the bits, such as, for example, the depth, location, and number of key notches along a top portion of a key blade, is typically designed to control the displacement of components of the lock mechanism. Thus, when a key having the appropriate bitting configuration is inserted into the key slot of the mating lock, the bitting configuration may displace components of the lock mechanism so that the key may be used to rotate a component of the lock mechanism, such as, for example, a plug body that is operably connected to a lock device. Moreover, such rotation may be used to operate a lock device that is operably connected to the lock mechanism, such as, for example, a deadbolt.
One example of a lock mechanism that utilizes the bittings on a key in connection with operating a lock device is a tumbler pin lock mechanism. More specifically, tumbler pin lock mechanisms may utilize retention pins to control whether a plug body of a lock mechanism may be rotated about a shear line. Moreover, when properly inserted into the key slot, the bittings of a key may engage and displace tumbler pins to positions in which tumbler pins that are adjacent to the shear line do not extend across the operating shear line. With tumbler pins properly aligned with the shear line, a plug body of the lock mechanism may be rotated as the key is rotated, thereby operably displacing the attached lock mechanism.
Presently, key top notching is typically done at regular intervals along a key blade, such as, for example, at a repeated distance of 0.15 inches from a center line of a first key notch to the center line of a second, adjacent key notch. Moreover, key notching is often performed in accordance with a particular key system, which may define, for example, the number of bittings to be employed and the spacing between the bittings. Traditionally, such systems, and the associated rules of those systems, may determine the number of possible key cut combinations, and more specifically, the number of available bitting configurations. For example, the number of possible bitting configurations may be the number of key notch depths raised to a power that is equal to the number of cuts or key notches. Thus, if a system has four key notch depths and uses three cuts or key notches, then the number of possible bitting configurations may be four to the power of three. Therefore, the number of possible key notch configurations for such systems are typically dependent on key notch depths.